If it tends to be sore with walking it could be a problem with poor circulation. Sometimes a cholesterol lowering medication can make them sore. A condition known as spinal stenosis where in the nerves are compressed in the lower vertebral column can make them sore as well. New heels or unaccustomed exercise (such as if you stared jogging or doing squats can cause muscle soreness. More info pl

It could be the result of recent activities and you have made the muscles sore from exercise (mountain climbing, stairs, etc.

) or could be from medications that cause muscle soreness. There could be a bruise from a direct blow. You could possibly have a clot in the calf and this is serious. There are other less common causes of leg muscle soreness. If concerned see your pcp right away.

In brief:
Several possibilitie

It could be the result of recent activities and you have made the muscles sore from exercise (mountain climbing, stairs, etc.

) or could be from medications that cause muscle soreness. There could be a bruise from a direct blow. You could possibly have a clot in the calf and this is serious. There are other less common causes of leg muscle soreness. If concerned see your pcp right away.
Would you like to video or text chat with me?